Heat sink



FIG. 1 is a perspective view of a heat sink showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a right side view thereof;

FIG. 5is a left side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof;

FIG. 8 is a top view depicting a reference line “A”; and,

FIG. 9 is a sectional view along reference line A.

Any shading shown represents a contrast in appearance for illustrative purposes and forms no part of the claimed design and does not depict any specific color, material, or texture. 

CLAIM The ornamental design for a heat sink, as shown and described. 